[Python] How can I plot two helicoids without a jump between surfaces?

Using matplotlib surface plot, I am plotting two right, helicoids. I have the surfaces as a single mesh however this makes an unwanted jump between the two surfaces.

Helicoid pair with jumps and poor surface face colormap:

import numpy as np
import matplotlib as mpl
import matplotlib.pyplot as plt

u = np.linspace(-np.pi, np.pi, 200)
v = np.linspace(np.pi, -np.pi, 200)

theta = np.pi
U, V = np.meshgrid(u, v)

X = np.cos(theta)*np.sinh(V)*np.sin(U) + np.sin(theta)*np.cosh(V)*np.cos(U)
Y = -np.cos(theta)*np.sinh(V)*np.cos(U) + np.sin(theta)*np.cosh(V)*np.sin(U)
Z = U*np.cos(theta)+V*np.sin(theta)


i = -1
for j in np.linspace(0,.8, 2):
X = np.append(X, X[::i,:], axis = 0)
Y = np.append(Y, Y[::i,:], axis = 0)
Z = np.append(Z, Z[::i,:]+j, axis = 0)
i *=-1

r_cols = (X**2 + Y**2)
r_cols /= np.max(r_cols)
r_cols = cm.jet(r_cols)


fig, ax = plt.subplots(figsize=(5,5), subplot_kw={"projection": "3d"})


ax.plot_surface(X, Y, Z, vmin=Z.min() * 2, facecolors = r_cols, rstride = 1 , linewidth=0 )

ax.set(xticklabels=[],
yticklabels=[],
zticklabels=[])
ax.view_init(elev=5, azim=40, roll=0)

plt.show()
fig.savefig('file{}.png'.format(num))
num +=1


I have tried to stack u to route back to the helical axis such as:

u = np.append(np.linspace(0, -np.pi, 200), np.linspace(-np.pi, np.pi, 200))
u = np.append(u,np.linspace(np.pi,0, 200))


as well as changing the way I stacked and added to Z

invert = -1
revert = 1
for j in np.linspace(0,.8, 2):
X = np.append(X, X[::invert,::revert], axis = 0)
Y = np.append(Y, Y[::invert,::revert], axis = 0)
Z = np.append(Z, Z[::invert,::revert]+j, axis = 0)
invert *=-1
revert *=-1

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